Glass compositions, fiberizable glass compositions, and glass fibers made therefrom

ABSTRACT

Glass compositions suitable for fiber forming having low levels of Li 2 O and glass fibers having high-modulus are disclosed. The glass composition may include SiO 2  from about 59 to about 63 weight percent, Al 2 O 3  from about 13.7 to about 16 weight percent, CaO from about 14 to about 16.5 weight percent, MgO from about 6 to about 8.5 weight percent, Fe 2 O 3  less than 1 weight percent, and TiO 2  less than 1 weight percent. In some cases, the composition may be substantially free of Li 2 O. In some cases, the composition may include Li 2 O up to 0.5 weight percent. In some cases, RE 2 O 3  may be present in the composition in an amount up to 1.5 weight percent. The glass compositions can be used to form glass fibers which can be incorporated into a variety of other fiber glass products (e.g., strands, rovings, fabrics, etc.) and incorporated into various composites.

PRIORITY

This application claims the benefit of and priority to U.S. ProvisionalPatent Application No. 62/639,731, filed Mar. 7, 2018, which is herebyincorporated herein by reference in its entirety as though fully setforth herein.

FIELD

Described herein are glass compositions, and in particular, glasscompositions for forming fibers.

BACKGROUND

Glass fibers have been used to reinforce various polymeric resins formany years. Some commonly used glass compositions for use inreinforcement applications include the “E-glass,” “R-glass,” and“D-glass” families of compositions. “S-glass” is another commonly usedfamily of glass compositions that includes, for example, glass fiberscommercially available from AGY (Aiken, S.C.) under the trade name “S-2Glass.”

Glass fibers fall into two categories: general purpose and specialpurpose. The most widely used glass fiber types are general purpose,also known as E-Glass fibers. Overall E-Glass offers good mechanical,electrical and corrosion properties.

As the possible market applications of composites continue to grow,users of glass fibers have faced challenges to meet the demands relatedto performance, cost, reliability and durability, as well as theincreased focus on sustainability and environmental stewardship.Included among the challenges are: the length requirements of windblades continue to grow; power plants want maximum performance andlifetime from pipes and tanks in harsh conditions and environments;demands for fuel economy with sacrifice of performance are bringingchanges to the automotive industry; and continued advancements intechnology require the signal speed of circuit boards to be more robustthan ever before.

Fiber glass manufacturers continue to seek glass compositions that canbe used to form glass fibers having desirable mechanical properties in acommercial manufacturing environment.

SUMMARY

Various embodiments of the present invention provide glass compositions,fiberizable glass compositions, and glass fibers formed from suchcompositions, as well as fiber glass strands, yarns, fabrics, andcomposites comprising such glass fibers adapted for use in variousapplications.

In an embodiment, a glass composition suitable for fiber forming maycomprise SiO₂ from about 60 to about 63 weight percent, Al₂O₃ from about14 to about 16 weight percent, CaO from about 14 to about 16 weightpercent, MgO from about 6 to about 8.5 weight percent, Fe₂O₃ less than 1weight percent, and TiO₂ less than 1 weight percent, where thecomposition is substantially free of Li₂O and the (Li₂O+MgO+Al₂O₃)content ranges from about 22 up to 24 weight percent.

In certain embodiments, a glass composition suitable for fiber formingmay comprise SiO₂ from about 60 to about 63 weight percent, Al₂O₃ fromabout 14 to about 16 weight percent, CaO from about 14 to about 16weight percent, MgO from about 6 to about 8.5 weight percent, Fe₂O₃ lessthan 1 weight percent, TiO₂ less than 1 weight percent, and rare earthoxide, RE₂O₃ in an amount greater than 0 weight percent and less than 1weight percent, where the composition is substantially free of Li₂O.

In certain embodiments, a glass composition suitable for fiber formingmay comprise SiO₂ from about 59 to about 63 weight percent, Al₂O₃ fromabout 13.7 to about 16 weight percent, CaO from about 14 to about 16.5weight percent, MgO from about 6 to about 8.5 weight percent, Fe₂O₃ lessthan 1 weight percent, TiO₂ less than 1 weight percent, and rare earthoxide, RE₂O₃ in an amount greater than 0 weight percent and less than1.5 weight percent, where the composition is substantially free of Li₂O.

In some cases, a glass composition suitable for fiber forming maycomprise SiO₂ from about 60 to about 63 weight percent, Al₂O₃ from about14 to about 16 weight percent, CaO from about 14 to about 16 weightpercent, MgO from about 6 to about 8.5 weight percent, Fe₂O₃ less than 1weight percent, TiO₂ less than 1 weight percent, Li₂O less than 0.5weight percent, and RE₂O₃ is present in an amount greater than 0 weightpercent and less than 1 weight percent, where the (Li₂O+MgO+Al₂O₃)content ranges from about 22 up to 24 weight percent.

In some embodiments, a glass composition suitable for fiber forming maycomprise SiO₂ from about 60 to about 63 weight percent, Al₂O₃ from about14 to about 16 weight percent, CaO from about 14 to about 16 weightpercent, MgO from about 6 to about 8.5 weight percent, Fe₂O₃ less than 1weight percent, TiO₂ less than 1 weight percent, and Li₂O is present inan amount greater than 0 weight percent and less than 0.5 weightpercent, where the (Li₂O+MgO+Al₂O₃) content ranges from about 22 up to23 weight percent.

In any of the foregoing embodiments, additional embodiments may includean Al₂O₃/(Al₂O₃+MgO+CaO) ratio range between 0.33 to 0.47. In certainembodiments, the Al₂O₃/(Al₂O₃+MgO+CaO) ratio may be less than 0.40. Insome embodiments, the Al₂O₃/(Al₂O₃+MgO+CaO) ratio may range from 0.37 to0.42. In some embodiments, the Al₂O₃/(Al₂O₃+MgO+CaO) ratio may rangefrom 0.35 to 0.45.

Some embodiments of the present invention relate to fiber glass strands.A number of fiberizable glass compositions are disclosed herein as partof the present invention, and it should be understand that variousembodiments of the present invention can comprise glass fibers, fiberglass strands, yarns, and other products incorporating glass fibersformed from such compositions. In one embodiment, a plurality of glassfibers formed from a glass composition may comprise SiO₂ from about 60to about 63 weight percent, Al₂O₃ from about 14 to about 16 weightpercent, CaO from about 14 to about 16 weight percent, MgO from about 6to about 8.5 weight percent, Fe₂O₃ less than 1 weight percent, TiO₂ lessthan 1 weight percent, and Li₂O is present in an amount greater than 0weight percent and less than 0.5 weight percent, where the(Li₂O+MgO+Al₂O₃) content ranges from about 22 up to 24 weight percentand the Young's modulus is greater than 85 GPa.

Some embodiments of the present invention relate to yarns formed from atleast one fiber glass strand formed from a glass composition describedherein. Some embodiments of the present invention relate to fabricsincorporating at least one fiber glass strand formed from a glasscomposition described herein. In some embodiments, a fill yarn used inthe fabric can comprise the at least one fiber glass strand. A warpyarn, in some embodiments, can comprise the at least one fiber glassstrand. In some embodiments, fiber glass strands can be used in bothfill yarns and warp yarns to form fabrics according to the presentinvention. In some embodiments, fabrics of the present invention cancomprise a plain weave fabric, twill fabric, crowfoot fabric, satinweave fabric, stitch bonded fabric, or 3D woven fabric.

Some embodiments of the present invention relate to compositescomprising a polymeric resin and glass fibers formed from one of thevarious glass compositions described herein. The glass fibers can befrom a fiber glass strand according to some embodiments of the presentinvention. In some embodiments, the glass fibers can be incorporatedinto a fabric, such as a woven fabric. For example, the glass fibers canbe in a fill yarn and/or a warp yarn that are woven to form a fabric. Inembodiments where the composite comprises a fabric, the fabric cancomprise a plain weave fabric, twill fabric, crowfoot fabric, satinweave fabric, stitch bonded fabric, or 3D woven fabric.

The glass fibers can be incorporated into the composite in other formsas well as discussed in more detail below.

Composites of the present invention may comprise one or more of avariety of polymeric resins. In some embodiments, the polymeric resinmay comprise at least one of polyethylene, polypropylene, polyamide,polyimide, polybutylene terephthalate, polycarbonate, thermoplasticpolyurethane, phenolic, polyester, vinyl ester, polydicyclopentadiene,polyphenylene sulfide, polyether ether ketone, cyanate esters,bis-maleimides, and thermoset polyurethane resins. The polymeric resincan comprise an epoxy resin in some embodiments.

Composites of the present invention can be in a variety of forms and canbe used in a variety of applications. Some examples of potential uses ofcomposites according to some embodiments of the present inventioninclude, without limitation, wind energy (e.g., windmill blades),automotive applications, safety/security applications (e.g., ballisticsarmor), aerospace or aviation applications (e.g., interior floors ofplanes), high pressure vessels or tanks, missile casings, electronics,and others.

These and other embodiments of the present invention are described ingreater detail in the Detailed Description that follows.

DETAILED DESCRIPTION OF THE INVENTION

Embodiments of the present invention relates generally to glasscompositions. In one aspect, the present invention provides glass fibersformed from glass compositions described herein. Specifically, the glasscompositions described herein may be free of Li₂O. Optionally, thecompositions may comprise low amounts of lithium oxide (Li₂O). In somecases, the glass compositions may comprise one or more rare earth oxide(RE₂O₃). In some embodiments, glass fibers of the present invention canhave improved mechanical properties, such as, for example, Young'smodulus, as compared to conventional E-glass fibers. In someembodiments, the glass fibers may have a modulus greater than 85 GPa. Incertain embodiments, the glass fibers may have a modulus greater than 88GPa. In some embodiments, the glass fibers may have a density less than2.7 g/cm³. In certain embodiments, the glass fibers may have a formingtemperature (T_(F)) of less than 1350° C. In some embodiments, the glassfibers may have a liquidus temperature (T_(L)) of less than 1250° C. Insome embodiments of glass compositions, the difference between the T_(F)and the T_(F) (“Delta T”) may be greater than about 60° C. In certainembodiments, the glass compositions may have a melt temperature (T_(M))of less than 1530° C.

Definitions and Descriptions

The terms “invention,” “the invention,” “the present invention,”“embodiment,” “certain embodiment,” and the like are used herein areintended to refer broadly to all the subject matter of this patentapplication and the claims below. Statements containing these termsshould be understood not to limit the subject matter described herein orto limit the meaning or scope of the patent claims below. The terms“comprising,” “having,” “including,” and “containing” are to beconstrued as open-ended terms (i.e., meaning “including, but not limitedto”) unless otherwise noted. It is further noted that, as used in thisspecification, the singular forms “a,” “an,” and “the” include pluralreferents unless expressly and unequivocally limited to one referent.

Notwithstanding that the numerical ranges and parameters setting forththe broad scope of the invention are approximations, the numericalvalues set forth in the specific examples are reported as precisely aspossible. Any numerical value, however, inherently contains certainerrors necessarily resulting from the standard deviation found in theirrespective testing measurements. Moreover, all ranges disclosed hereinare to be understood to encompass any and all subranges subsumedtherein. For example, a stated range of “1 to 10” should be consideredto include any and all subranges between (and inclusive of) the minimumvalue of 1 and the maximum value of 10; that is, all subranges beginningwith a minimum value of 1 or more, e.g. 1 to 6.1, and ending with amaximum value of 10 or less, e.g., 5.5 to 10. Additionally, anyreference referred to as being “incorporated herein” is to be understoodas being incorporated in its entirety.

The glass compositions are described in terms of weight percentage (wt.%) based on the total weight of the composition.

Glass Compositions and Fibers

The invention may be embodied in a variety of ways. In some embodiments,a glass composition suitable for fiber forming may comprise SiO₂, Al₂O₃,CaO, MgO, Fe₂O₃, and TiO₂. Optionally, the composition may furthercomprise RE₂O₃. Optionally, the composition may further comprise Li₂O.In some embodiments, the composition may be substantially free of Li₂O.

In certain embodiments, the glass composition suitable for fiber formingas described herein may comprise SiO₂ from about 59 to about 63 weightpercent (e.g., 60 wt. % to 63 wt. %). For example, the composition mayinclude SiO₂ in an amount of about 59 wt. %, 59.1 wt. %, 59.2 wt. %,59.3 wt. %, 59.4 wt. %, 59.5 wt. %, 59.6 wt. %, 59.7 wt. %, 59.8 wt. %,59.9 wt. %, 60 wt. %, 60.1 wt. %, 60.2 wt. %, 60.3 wt. %, 60.4 wt. %,60.5 wt. %, 60.6 wt. %, 60.7 wt. %, 60.8 wt. %, 60.9 wt. %, 61 wt. %,61.1 wt. %, 61.2 wt. %, 61.3 wt. %, 61.4 wt. %, 61.5 wt. %, 61.6 wt. %,61.7 wt. %, 61.8 wt. %, 61.9 wt. %, 62 wt. %, 62.1 wt. %, 62.2 wt. %,62.3 wt. %, 62.4 wt. %, 62.5 wt. %, 62.6 wt. %, 62.7 wt. %, 62.8 wt. %,62.9 wt. %, or 63 wt. %.

In some examples, the glass composition suitable for fiber forming asdescribed herein may comprise Al₂O₃ from about 13.7 to about 16.5 weightpercent (e.g., 14 wt. % to 16 wt. %). For example, the composition mayinclude Al₂O₃ in an amount of about 13.7, 13.8, 13.9, 14 wt. %, 14.1 wt.%, 14.2 wt. %, 14.3 wt. %, 14.4 wt. %, 14.5 wt. %, 14.6 wt. %, 14.7 wt.%, 14.8 wt. %, 14.9 wt. %, 15 wt. %, 15.1 wt. %, 15.2 wt. %, 15.3 wt. %,15.4 wt. %, 15.5 wt. % 15.6 wt. %, 15.7 wt. %, 15.8 wt. %, 15.9 wt. %,16 wt. %, 16.1 wt. %, 16.2 wt. %, 16.3 wt. %, 16.4 wt. %, or 16.5 wt. %.

In some embodiments, the glass composition suitable for fiber forming asdescribed herein may comprise CaO from about 14 to about 16.5 weightpercent (e.g., 14 wt. % to 16 wt. %). For example, the composition mayinclude CaO in an amount of about 14 wt. %, 14.1 wt. %, 14.2 wt. %, 14.3wt. %, 14.4 wt. %, 14.5 wt. %, 14.6 wt. %, 14.7 wt. %, 14.8 wt. %, 14.9wt. %, 15 wt. %, 15.1 wt. %, 15.2 wt. %, 15.3 wt. %, 15.4 wt. %, 15.5wt. % 15.6 wt. %, 15.7 wt. %, 15.8 wt. %, 15.9 wt. %, 16 wt. %, 16.1 wt.%, 16.2 wt. %, 16.2 wt. %, 16.4 wt. %, or 16.5 wt. %.

In some embodiments, the glass composition suitable for fiber forming asdescribed herein may comprise MgO from about 6 to about 8.5 weightpercent (e.g., 6 wt. % to 8 wt. %). For example, the composition mayinclude MgO in an amount of about 6 wt. %, 6.1 wt. %, 6.2 wt. %, 6.3 wt.%, 6.4 wt. %, 6.5 wt. %, 6.6 wt. %, 6.7 wt. %, 6.8 wt. %, 6.9 wt. %, 7wt. %, 7.1 wt. %, 7.2 wt. %, 7.3 wt. %, 7.4 wt. %, 7.5 wt. %, 7.6 wt. %,7.7 wt. %, 7.8 wt. %, 7.9 wt. %, 8 wt. %, 8.1 wt. %, 8.2 wt. %, 8.3 wt.%, 8.4 wt. %, or 8.5 wt. %.

In some embodiments, the glass composition suitable for fiber forming asdescribed herein may comprise Fe₂O₃ in an amount less than 1 weightpercent. For example, the composition may include Fe₂O₃ in an amount ofabout 0.25 wt. %, 0.3 wt. %, 0.35 wt. %, 0.4 wt. %, 0.45 wt. %, 0.5 wt.%, 0.55 wt. %, 0.6 wt. %, 0.65 wt. %, 0.7 wt. %, 0.75 wt. %, 0.8 wt. %,0.85 wt. %, 0.9 wt. %, 0.95 wt. %, or up to 1.0 wt. %. In some cases,the composition may be substantially free of Fe₂O₃.

In some embodiments, the glass composition suitable for fiber forming asdescribed herein may comprise TiO₂ in an amount less than 1 weightpercent. For example, the composition may include TiO₂ in an amount ofabout 0.25 wt. %, 0.3 wt. %, 0.35 wt. %, 0.4 wt. %, 0.45 wt. %, 0.5 wt.%, 0.55 wt. %, 0.6 wt. %, 0.65 wt. %, 0.7 wt. %, 0.75 wt. %, 0.8 wt. %,0.85 wt. %, 0.9 wt. %, 0.95 wt. %, or up to 1.0 wt. %. In some cases,the composition may be substantially free of TiO₂.

Optionally, some embodiments of the glass composition suitable for fiberforming as described herein may comprise Li₂O in an amount less than 0.5weight percent (e.g., less than 0.4 wt. %). For example, the compositionmay include Li₂O in an amount of about 0.05 wt. %, 0.1 wt. %, 0.15 wt.%, 0.2 wt. %, 0.25 wt. %, 0.3 wt. %, 0.35 wt. %, 0.4 wt. %, 0.45 wt. %,or 0.5 wt %. In some cases, the composition may be substantially free ofLi₂O.

Optionally, some embodiments of the glass composition suitable for fiberforming as described herein may comprise rare earth oxides (“RE₂O₃”) inan amount less than 1 weight percent. In some embodiments, the glasscomposition may comprise RE₂O₃ in an amount less than 1.5 weightpercent. For example, the composition may include RE₂O₃ in an amount ofabout 0.2 wt. %, 0.25 wt. %, 0.3 wt. %, 0.35 wt. %, 0.4 wt. %, 0.45 wt.%, 0.5 wt. %, 0.55 wt. %, 0.6 wt. %, 0.65 wt. %, 0.7 wt. %, 0.75 wt. %,0.8 wt. %, 0.85 wt. %, 0.9 wt. %, 0.95 wt. %, 1.0 wt. %, 1.1 wt. %, 1.2wt. %, 1.3 wt. %, 1.4 wt. %, or up to 1.5 wt. %. As used herein, theterm “rare earth oxides” as understood to those of skill in the art,refers to oxides incorporating a rare earth metal and includes oxides ofscandium (Sc₂O₃), yttrium (Y₂O₃), and the lanthanide elements (lanthanum(La₂O₃), cerium (Ce₂O₃ and CeO₂), praseodymium (Pr₂O₃), neodymium(Nd₂O₃), promethium (Pm₂O₃), samarium (Sm₂O₃), europium (Eu₂O₃ and EuO),gadolinium (Gd₂O₃), terbium (Tb₂O₃), dysprosium (Dy₂O₃), holmium(Ho₂O₃), erbium (Er₂O₃), thulium (Tm₂O₃), ytterbium (Yb₂O₃), andlutetium (Lu₂O₃). The rare earth oxides may be included in the glasscompositions of the present invention in amounts that exceed thosewherein the rare earth oxide is present only as a tramp material orimpurity in a batch material included with a glass batch to provideanother component. The glass compositions, in some embodiments, cancomprise a combination of rare earth oxides (e.g., one or more ofvarious rare earth oxides). In some embodiments, RE₂O₃ may comprise atleast one of La₂O₃, Y₂O₃, Sc₂O₃, and Nd₂O₃. In some embodiments, RE₂O₃may be Y₂O₃. In some embodiments, the Y₂O₃ content can be about 1 weightpercent or less. In some cases, RE₂O₃ may be present in an amountgreater than 0 weight percent and less than 1.5 weight percent. In somecases, the composition may be substantially free of RE₂O₃.

Not intending to be bound by theory, the inclusion of Y₂O₃ in glasscompositions may have a desirable impact on glass softening temperatureand glass transition temperature as well as on modulus, tensilestrength, elongation, coefficient of thermal expansion, and otherproperties of glass fibers formed from the compositions.

In some embodiments, the glass composition suitable for fiber forming asdescribed herein may comprise (Li₂O+MgO+Al₂O₃) from about 22 up to 23weight percent. In some embodiments, the glass composition suitable forfiber forming may comprise (Li₂O+MgO+Al₂O₃) from about 22 up to 24weight percent. For example, the composition may include(Li₂O+MgO+Al₂O₃) in an amount of about 22 wt. %, 22.1.1 wt. %, 22.2 wt.%, 22.3 wt. %, 22.4 wt. %, 22.5 wt. %, 22.6 wt. %, 22.7 wt. %, 22.8 wt.%, 22.9 wt. %, 23 wt. %, 23.1 wt. %, 23.2 wt. %, 23.3 wt. %, 23.4 wt. %,23.5 wt. %, 23.6 wt. %, 23.7 wt. %, 23.8 wt. %, 23.9, or 24 wt %.

In some embodiments, the glass composition suitable for fiber forming asdescribed herein may comprise a ratio of CaO to MgO (“CaO/MgO”) fromabout 1.6 to about 2.8 (e.g., 1.7 to 2.0). For example, the compositionmay include CaO/MgO in an amount of about 1.6, 1.65, 1.7, 1.75, 1.8,1.85, 1.9, 1.95, 2.0, 2.15, 2.2, 2.25, 2.3, 2.35, 2.4, 2.45, 2.5, 2.55,2.6, 2.65, 2.7, 2.75, or 2.8.

In some embodiments, the glass composition suitable for fiber forming asdescribed herein may comprise a ratio of SiO₂ to Al₂O₃ (“SiO₂/Al₂O₃”)from about 3.5 to about 4.6 (e.g., from about 3.9 to about 4.3, fromabout 4 to about 4.5, from greater than 4 to 4.5). For example, thecomposition may include SiO₂/Al₂O₃ in an amount of about 3.5, 3.55, 3.6,3.65, 3.7, 3.75, 3.8, 3.85, 3.9, 3.95, 4, 4.05, 4.1, 4.15, 4.2, 4.25,4.3, 4.35, 4.4, 4.45, 4.5, 4.55, or 4.6. In some embodiments, theSiO₂/Al₂O₃ may be greater than 4.

In some embodiments, the glass composition suitable for fiber forming asdescribed herein may comprise a ratio of Al₂O₃ to (Al₂O₃+CaO+MgO)(“Al₂O₃/(Al₂O₃+CaO+MgO)”) from about 0.33 to about 0.47 (e.g., fromabout 0.35 to about 0.41, from about 0.35 to less than 0.40). Forexample, the composition may include Al₂O₃/(Al₂O₃+CaO+MgO) in an amountof about 0.33, 0.34, 0.35, 0.36, 0.37, 0.38, 0.39, 0.40, 0.41, 0.42,0.43, 0.44, 0.45, 0.46, or 0.47. In some embodiments, theAl₂O₃/(Al₂O₃+CaO+MgO) may be less than 0.40. In other embodiments, theAl₂O₃/(Al₂O₃+MgO+CaO) ratio may range from 0.37 to 0.42.

In some embodiments, the glass composition may comprise up to 0.2 weightpercent Na₂O. In some cases, the composition may be substantially freeof Na₂O. In certain embodiments, the glass composition may comprise upto 0.2 weight percent K₂O. In some cases, the composition may besubstantially free of K₂O. In some embodiments, the glass compositionmay be substantially free of at least one of Zn, F, B, or Sr.

In some embodiments, the glass composition suitable for fiber formingmay comprise: SiO₂ from about 60 to about 63 weight percent; Al₂O₃ fromabout 14 to about 16 weight percent; CaO from about 14 to about 16weight percent; MgO from about 6 to about 8.5 weight percent; Fe₂O₃ lessthan 1 weight percent; and TiO₂ less than 1 weight percent. In someembodiments, the composition may be substantially free of Li₂O. In someembodiments, the (Li₂O+MgO+Al₂O₃) content may ranges from about 22 up to24 weight percent.

In some cases, the glass composition suitable for fiber forming maycomprise: SiO₂ from about 60 to about 63 weight percent; Al₂O₃ fromabout 14 to about 16 weight percent; CaO from about 14 to about 16weight percent; MgO from about 6 to about 8.5 weight percent; Fe₂O₃ lessthan 1 weight percent; TiO₂ less than 1 weight percent; and RE₂O₃present in an amount greater than 0 weight percent and less than 1weight percent. In some embodiments, the composition may besubstantially free of Li₂O.

In certain embodiments, a glass composition suitable for fiber formingmay comprise SiO₂ from about 59 to about 63 weight percent, Al₂O₃ fromabout 13.7 to about 16 weight percent, CaO from about 14 to about 16.5weight percent, MgO from about 6 to about 8.5 weight percent, Fe₂O₃ lessthan 1 weight percent, TiO₂ less than 1 weight percent, and rare earthoxide, RE₂O₃ in an amount greater than 0 weight percent and less than1.5 weight percent, where the composition is substantially free of Li₂O.

In certain embodiments, the glass composition suitable for fiber formingmay comprise: SiO₂ from about 60 to about 63 weight percent; Al₂O₃ fromabout 14 to about 16 weight percent; CaO from about 14 to about 16weight percent; MgO from about 6 to about 8.5 weight percent; Fe₂O₃ lessthan 1 weight percent; TiO₂ less than 1 weight percent; Li₂O less than0.5 weight percent; and RE₂O₃ present in an amount greater than 0 weightpercent and less than 1 weight percent. In some embodiments, the(Li₂O+MgO+Al₂O₃) content may range from about 22 up to 24 weightpercent.

In some embodiments, the glass composition suitable for fiber formingmay comprise: SiO₂ from about 60 to about 63 weight percent; Al₂O₃ fromabout 14 to about 16 weight percent; CaO from about 14 to about 16weight percent; MgO from about 6 to about 8.5 weight percent; Fe₂O₃ lessthan 1 weight percent; TiO₂ less than 1 weight percent; and Li₂O presentin an amount greater than 0 weight percent and less than 0.5 weightpercent. In some embodiments, the (Li₂O+MgO+Al₂O₃) content ranges fromabout 22 up to 23 weight percent.

It should be understood that any component of a glass compositiondescribed as being present in amount from about 0 weight percent toanother weight percent is not necessarily required in all embodiments.Such components may be optional in some embodiments. Likewise, in someembodiments, glass compositions can be substantially free of somecomponents; any amount of the component present in the glass compositionwould result from the component being present as a trace impurity in abatch material. A component present as a trace impurity is notintentionally added to the glass composition, but rather, it may bepresent in a herein described glass composition by virtue of itspresence as an impurity in a starting material added to the glasscomposition. Generally, a trace impurity is present in the glasscomposition in an amount no greater than about 0.1 weight percent,although some trace impurities may be present in the glass compositionin an amount up to about 0.5 weight percent.

In some embodiments, the glass compositions of the present invention maybe fiberizable. In some embodiments, glass compositions may have formingtemperatures (T_(F)) desirable for use in commercial fiber glassmanufacturing operations. As used herein, the term “forming temperature”or T_(F), means the temperature at which the glass composition has aviscosity of 1000 poise (or “log 3 temperature”). In some embodiments,the glass compositions may have a forming temperature (T_(F)) less than1350° C. (e.g., less than 1320° C., less than 1300). By way of example,rounded to the nearest 5° C., the T_(F) may be about 1200° C., 1205° C.,1210° C., 1215° C., 1220° C., 1225° C., 1230° C., 1235° C., 1240° C.,1245° C., 1250° C., 1255° C., 1260° C., 1265° C., 1270° C., 1275° C.,1280° C., 1285° C., 1290° C., 1295° C., 1300° C., 1305° C., 1310° C.,1315° C., 1320° C., 1325° C., 1330° C., 1335° C., 1340° C., 1345° C., orup to 1350° C.

In some embodiments, the glass compositions may have a liquidustemperature (T_(L)) of less than 1250° C. (e.g., less than 1220° C.,less than 1200). For example, rounded to the nearest 5° C., the T_(L)may be about 1120° C., 1125° C., 1130° C., 1135° C., 1140° C., 1145° C.,1150° C., 1155° C., 1160° C., 1165° C., 1170° C., 1175° C., 1180° C.,1185° C., 1190° C., 1195° C., 1200° C., 1205° C., 1210° C., 1215° C.,1220° C., 1225° C., 1230° C., 1235° C., 1240° C., 1245° C., or up to1250° C.

In some embodiments, the difference between the forming temperature(T_(F)) and the liquidus temperature (T_(L)) of a glass composition maybe desirable for commercial fiber glass manufacturing operations. Forexample, in some embodiments of glass compositions, the differencebetween the T_(F) and the T_(F) (“Delta T”) may be greater than about60° C. (e.g., greater than 80° C., greater than 100). For example, theDelta T may be about 62° C., 64° C., 66° C., 68° C., 70° C., 72° C., 74°C., 76° C., 78° C., 80° C., 82° C., 84° C., 86° C., 88° C., 90° C., 92°C., 94° C., 96° C., 98° C., 100° C., 105° C., 110° C., 115° C., or 120°C.

In some embodiments, the glass compositions may have a melt temperature(T_(M)) of less than 1530° C. (e.g., less than 1510° C., less than 1480°C.). For example, the T_(M) may be about 1465° C., 1468° C., 1470° C.,1472° C., 1474° C., 1476° C., 1478° C., 1480° C., 1482° C., 1484° C.,1486° C., 1488° C., 1490° C., 1492° C., 1494° C., 1496° C., 1498° C.,1500° C., 1502° C., 1504° C., 1506° C., 1508° C., 1510° C., 1512° C.,1514° C., 1516° C., 1518° C., 1520° C., 1522° C., 1524° C., 1526° C.,1528° C., or 1530° C.

In some embodiments, glass fibers may be formed from the glasscompositions described herein. Optionally, the glass fibers may bearranged into a fabric. In some embodiments, glass fibers may beprovided in other forms including, for example and without limitation,as continuous strands, chopped strands (dry or wet), yarns, rovings,prepregs, etc. Various embodiments of the glass compositions (and anyfibers formed therefrom) may be used in a variety of applications. Insome embodiments, the fibers may be fiber glass strands, while otherembodiments may be yarns comprising fiber glass strands. Someembodiments of yarns may be particularly suitable for weavingapplications. In some embodiments, the fibers may be glass fiberfabrics. Some embodiments of fiber glass fabrics of the presentinvention are particularly suitable for use in reinforcementapplications, especially reinforcement applications in which highmodulus, high strength, and/or high elongation are important.

Some embodiments of the present invention may relate to composites thatincorporate fiber glass strands, fiber glass yarns, and fiber glassfabrics, such as fiber reinforced polymer composites. Some compositesmay be particularly suitable for use in reinforcement applications,especially reinforcement applications in which high modulus, highstrength, and/or high elongation are important, such as wind energy(e.g., windmill blades), automotive applications, safety/securityapplications (e.g., ballistics armor or armor panels), aerospace oraviation applications (e.g., interior floors of planes), high pressurevessels or tanks, missile casings, and others.

Some embodiments of the present invention relate to composites suitablefor use in wind energy applications. Composites of the present inventioncan be suitable for use in wind turbine blades, particularly long windturbine blades that are lighter weight but still strong compared toother long wind turbine blades. Lower weight and increased stability inwind energy blades are key considerations for selection of compositematerials. The design of wind energy blades has changed over time topursue longer blades to harvest more energy. Some blades may be 82meters in length and benefit from improved fiber composites. A strongerglass fiber composite such as those disclosed herein may be useful toachieve a larger wind blade size while providing the strength and weightneeded to stay within the load design of windmill. Lighter and strongermaterials like the present invention may provide an increase in energyyield and result in improved operating costs, reduced installationcosts, ease of transportation, and improved safety.

Still other embodiments of the present invention may relate toautomotive composites. Some embodiments of the present invention mayrelate to aerospace composites. Other embodiments of the presentapplication may relate to aviation composites. Some embodiments of thepresent invention relate to composites for safety/security applicationssuch as armor panels. Other embodiments of the present invention mayrelate to composites for high pressure vessels or storage tanks. Someembodiments of the present invention may relate to composites formissile casings. Other embodiments of the present invention may relateto composites for use in high temperature thermal insulationapplications. Some embodiments of the present invention may relate toprinted circuit boards where lower coefficients of thermal expansion areparticularly desirable such as substrates for chip packaging. Someembodiments of the present invention may relate to prepreg. Someembodiments of the present invention may relate to long fiber reinforcedthermoplastics (LFT) for various automobile parts. Some embodiments ofthe present invention may relate to pipes or tanks for chemicaltransportation and chemical storage. Some embodiments of the presentinvention may relate to nonwoven, texturized fibers for thermal andsonic management applications, such as muffler for motorbikes, vehicles,and trucks. Some embodiments of the present invention may relate toelectrical insulating rods or cables. Some embodiments of the presentinvention may relate to composite rebar to replace steel rebar for roadinfrastructures, bridges, and buildings.

Some embodiments of the present invention relate to fiber glass strands.In some embodiments, a fiber glass strand of the present inventioncomprises a plurality of glass fibers. In some embodiments, a pluralityof glass fibers may be formed from the glass composition comprising:SiO₂ from about 60 to about 63 weight percent; Al₂O₃ from about 14 toabout 16 weight percent; CaO from about 14 to about 16 weight percent;MgO from about 6 to about 8.5 weight percent; Fe₂O₃ less than 1 weightpercent; and TiO₂ less than 1 weight percent. In some embodiments, thecomposition may be substantially free of Li₂O. In some embodiments, the(Li₂O+MgO+Al₂O₃) content of the composition may range from about 22 upto 24 weight percent. In some embodiments, the a ratio of CaO to MgO(CaO/MgO) of the composition may range from about 1.7 to about 2.0. Insome cases, the composition may be substantially free of F₂. In somecases, the composition may further comprise up to 0.2 weight percentNa₂O. In some cases, the composition may further comprise up to 0.2weight percent K₂O.

In some embodiments, a plurality of glass fibers may be formed from theglass composition comprising: SiO₂ from about 59 to about 63 weightpercent; Al₂O₃ from about 13.7 to about 16 weight percent; CaO fromabout 14 to about 16.5 weight percent; MgO from about 6 to about 8.5weight percent; Fe₂O₃ less than 1 weight percent; TiO₂ less than 1weight percent; and RE₂O₃ present in an amount greater than 0 weightpercent and less than 1.5 weight percent. In some embodiments, thecomposition may be substantially free of Li₂O. In some embodiments, the(Li₂O+MgO+Al₂O₃) content of the composition may range from about 22 upto 24 weight percent. In some embodiments, the a ratio of CaO to MgO(CaO/MgO) of the composition may range from about 1.6 to about 2.8. Insome cases, the composition may be substantially free of F₂. In somecases, the composition may further comprise up to 0.2 weight percentNa₂O. In some cases, the composition may further comprise up to 0.2weight percent K₂O.

In some embodiments, a glass fiber or a plurality of glass fibers may beformed from the glass composition comprising: SiO₂ from about 60 toabout 63 weight percent; Al₂O₃ from about 14 to about 16 weight percent;CaO from about 14 to about 16 weight percent; MgO from about 6 to about8.5 weight percent; Fe₂O₃ less than 1 weight percent; TiO₂ less than 1weight percent; Li₂O less than 0.5 weight percent; and RE₂O₃ is presentin an amount greater than 0 weight percent and less than 1 weightpercent. In some embodiments, the (Li₂O+MgO+Al₂O₃) content of thecomposition may range from about 22 up to 24 weight percent. In someembodiments, the a ratio of CaO to MgO (CaO/MgO) of the composition mayrange from about 1.7 to about 2.0. In some cases, the composition may besubstantially free of F₂. In some cases, the composition may furthercomprise up to 0.2 weight percent Na₂O. In some cases, the compositionmay further comprise up to 0.2 weight percent K₂O.

In some embodiments, a glass fiber or a plurality of glass fibers may beformed from the glass composition comprising: SiO₂ from about 60 toabout 63 weight percent; Al₂O₃ from about 14 to about 16 weight percent;CaO from about 14 to about 16 weight percent; MgO from about 6 to about8.5 weight percent; Fe₂O₃ less than 1 weight percent; TiO₂ less than 1weight percent; and Li₂O present in an amount greater than 0 weightpercent and less than 0.5 weight percent. In some embodiments, the(Li₂O+MgO+Al₂O₃) content may range from about 22 up to 23 weightpercent. In some embodiments, the a ratio of CaO to MgO (CaO/MgO) of thecomposition may range from about 1.7 to about 2.0. In some cases, thecomposition may be substantially free of F₂. In some cases, thecomposition may further comprise up to 0.2 weight percent Na₂O. In somecases, the composition may further comprise up to 0.2 weight percentK₂O.

In some embodiments, a glass fiber or a plurality of glass fibers may beformed from the glass composition comprising: SiO₂ from about 60 toabout 63 weight percent; Al₂O₃ from about 14 to about 16 weight percent;CaO from about 14 to about 16 weight percent; MgO from about 6 to about8.5 weight percent; Fe₂O₃ less than 1 weight percent; TiO₂ less than 1weight percent; and Li₂O present in an amount greater than 0 weightpercent and less than 0.5 weight percent. In some embodiments, the(Li₂O+MgO+Al₂O₃) content may range from about 22 up to 24 weightpercent. In some embodiments, the Young's modulus may be greater than 85GPa. In some embodiments, the Young's modulus may be greater than 88GPa. In some embodiments, the a ratio of CaO to MgO (CaO/MgO) of thecomposition may range from about 1.7 to about 2.0. In some cases, thecomposition may be substantially free of F₂. In some cases, thecomposition may further comprise up to 0.2 weight percent Na₂O. In somecases, the composition may further comprise up to 0.2 weight percentK₂O.

In some embodiments, a glass fiber or a plurality of glass fibers of thepresent invention may exhibit desirable mechanical and other properties.Glass fibers of the present invention, in some embodiments, can exhibitone or more improved mechanical properties relative to glass fibersformed from E-glass. In some embodiments, glass fibers of the presentinvention can provide one or more improved properties relative to glassfibers formed from R-glass and/or S-glass. Examples of desirableproperties exhibited by some embodiments of glass fibers of the presentinvention include, without limitation, tensile strength, Young'smodulus, coefficient of thermal expansion, softening point, elongation,and dielectric constant.

In some embodiments, a glass fiber or a plurality of glass fibers may beformed from the glass composition described herein. In certainembodiments, the plurality of glass fibers may have desirable Young'smodulus (E) values. In some cases, the plurality of glass fibers mayhave a Young's modulus greater than about 85 GPa (e.g., greater than 87GPa, greater than 88 GPa). For example, the Young's modulus may be about85 GPa, 85.1 GPa, 85.2 GPa, 85.3 GPa, 85.4 GPa, 85.5 GPa, 85.6 GPa, 85.7GPa, 85.8 GPa, 85.9 GPa, 86 GPa, 86.1 GPa, 86.2 GPa, 86.3 GPa, 86.4 GPa,86.5 GPa, 85.6 GPa, 86.7 GPa, 86.8 GPa, 86.9 GPa, 87 GPa, 87.1 GPa, 87.2GPa, 87.3 GPa, 87.4 GPa, 87.5 GPa, 87.6 GPa, 87.7 GPa, 87.8 GPa, 87.9GPa, 88 GPa, 88.1 GPa, 88.2 GPa, 88.3 GPa, 88.4 GPa, 88.5 GPa, 88.6 GPa,88.7 GPa, 88.8 GPa, 88.9 GPa, 89 GPa, 89.1 GPa, 89.2 GPa, 89.3 GPa, 89.4GPa, or 89.5 GPa. In some embodiments, the plurality of glass fibers mayhave a Young's modulus greater than about 90 GPa. In certainembodiments, the plurality of glass fibers may have a Young's modulus ofup to 95 GPa.

In certain embodiments, the glass fiber or plurality of glass fibers mayhave desirable density values. In some cases, the plurality of glassfibers may have a density less than about 2.7 g/cm³ (e.g., less than 2.6GPa, greater than 2.55 GPa). For example, the density may be about 2.55g/cm³, 2.56 g/cm³, 2.57 g/cm³, 2.58 g/cm³, 2.59 g/cm³, 2.6 g/cm³, 2.61g/cm³, 2.62 g/cm³, 2.63 g/cm³, 2.64 g/cm³, 2.65 g/cm³, 2.66 g/cm³, 2.67g/cm³, 2.68 g/cm³, 2.69 g/cm³, or 2.7 g/cm³.

Fiber glass strands can comprise glass fibers of various diameters,depending on the desired application. In some embodiments, a fiber glassstrand of the present invention may comprise at least one glass fiberhaving a diameter between about 5 and about 18 μm. In other embodiments,the at least one glass fiber has a diameter between about 5 and about 10μm. In some embodiments, fiber glass strands of the present inventioncan be formed into rovings. Rovings may comprise assembled, multi-end,or single-end direct draw rovings. Rovings comprising fiber glassstrands of the present invention can comprise direct draw single-endrovings having various diameters and densities, depending on the desiredapplication. In some embodiments, a roving comprising fiber glassstrands of the present invention exhibits a density up to about 112yards/pound. Some embodiments of the present invention relate to yarnscomprising at least one fiber glass strand as disclosed herein.

In some embodiments, a fiber glass strand may comprise the plurality ofglass fibers of any one of the glass compositions described herein. Forexample, in some embodiments, a fiber glass strand may comprise aplurality of glass fibers formed from the glass composition comprising:SiO₂ from about 60 to about 63 weight percent; Al₂O₃ from about 14 toabout 16 weight percent; CaO from about 14 to about 16 weight percent;MgO from about 6 to about 8.5 weight percent; Fe₂O₃ less than 1 weightpercent; and TiO₂ less than 1 weight percent. In some embodiments, thecomposition may be substantially free of Li₂O. In some cases, thecomposition may further comprise Li₂O less than 0.5 weight percent. Insome cases, Li₂O may be present in an amount greater than 0 weightpercent and less than 0.5 weight percent. In some embodiments, the(Li₂O+MgO+Al₂O₃) content of the composition may range from about 22 upto 24 weight percent. In some embodiments, the a ratio of CaO to MgO(CaO/MgO) of the composition may range from about 1.7 to about 2.0. Insome cases, the composition may be substantially free of F₂. In somecases, the composition may further comprise up to 0.2 weight percentNa₂O. In some cases, the composition may further comprise up to 0.2weight percent K₂O. In some cases, RE₂O₃ may be present in thecomposition in an amount greater than 0 weight percent and less than 1weight percent.

In other embodiments, a yarn of the present invention can comprise atleast one fiber glass strand comprising one of the other glasscompositions disclosed herein as part of the present invention.

In some embodiments, a yarn of the present invention may comprise atleast one fiber glass strand as disclosed herein, wherein the at leastone fiber glass strand is at least partially coated with a sizingcomposition. In some embodiments, the sizing composition may becompatible with a thermosetting polymeric resin. In other embodiments,the sizing composition can comprise a starch-oil sizing composition.

Yarns can have various linear mass densities, depending on the desiredapplication. In some embodiments, a yarn of the present invention mayhave a linear mass density from about 5,000 yards/pound to about 10,000yards/pound.

Yarns can have various twist levels and directions, depending on thedesired application. In some embodiments, a yarn of the presentinvention may have a twist in the z direction of about 0.5 to about 2turns per inch. In other embodiments, a yarn of the present inventionmay have a twist in the z direction of about 0.7 turns per inch.

Yarns can be made from one or more strands that are twisted togetherand/or plied, depending on the desired application. Yarns can be madefrom one or more strands that are twisted together but not plied; suchyarns are known as “singles.” Yarns of the present invention can be madefrom one or more strands that are twisted together but not plied. Insome embodiments, yarns of the present invention may comprise 1-4strands twisted together. In other embodiments, yarns of the presentinvention may comprise 1 twisted strand.

In some embodiments, a fiber glass strand may comprise the plurality ofglass fibers of any one of the glass compositions described herein. Forexample, in some embodiments, a fiber glass strand may comprise aplurality of glass fibers formed from the glass composition comprising:SiO₂ from about 59 to about 63 weight percent; Al₂O₃ from about 13.7 toabout 16 weight percent; CaO from about 14 to about 16.5 weight percent;MgO from about 6 to about 8.5 weight percent; Fe₂O₃ less than 1 weightpercent; and TiO₂ less than 1 weight percent. In some embodiments, thecomposition may be substantially free of Li₂O. In some cases, thecomposition may further comprise Li₂O less than 0.5 weight percent. Insome cases, Li₂O may be present in an amount greater than 0 weightpercent and less than 0.5 weight percent. In some embodiments, the(Li₂O+MgO+Al₂O₃) content of the composition may range from about 22 upto 24 weight percent. In some embodiments, the a ratio of CaO to MgO(CaO/MgO) of the composition may range from about 1.6 to about 2.8. Insome cases, the composition may be substantially free of F₂. In somecases, the composition may further comprise up to 0.2 weight percentNa₂O. In some cases, the composition may further comprise up to 0.2weight percent K₂O. In some cases, RE₂O₃ may be present in thecomposition in an amount greater than 0 weight percent and less than 1.5weight percent.

In some embodiments, a roving may comprise the plurality of glass fibersof any one of the glass compositions described herein. For example, insome embodiments, a roving may comprise a plurality of glass fibersformed from the glass composition comprising: SiO₂ from about 60 toabout 63 weight percent; Al₂O₃ from about 14 to about 16 weight percent;CaO from about 14 to about 16 weight percent; MgO from about 6 to about8.5 weight percent; Fe₂O₃ less than 1 weight percent; and TiO₂ less than1 weight percent. In some embodiments, the composition may besubstantially free of Li₂O. In some cases, the composition may furthercomprise Li₂O less than 0.5 weight percent. In some cases, Li₂O may bepresent in an amount greater than 0 weight percent and less than 0.5weight percent. In some embodiments, the (Li₂O+MgO+Al₂O₃) content of thecomposition may range from about 22 up to 24 weight percent. In someembodiments, the a ratio of CaO to MgO (CaO/MgO) of the composition mayrange from about 1.7 to about 2.0. In some cases, the composition may besubstantially free of F₂. In some cases, the composition may furthercomprise up to 0.2 weight percent Na₂O. In some cases, the compositionmay further comprise up to 0.2 weight percent K₂O. In some cases, RE₂O₃may be present in the composition in an amount greater than 0 weightpercent and less than 1 weight percent.

In some embodiments, a yarn may comprise the plurality of glass fibersof any one of the glass compositions described herein. For example, insome embodiments, a yarn may comprise a plurality of glass fibers formedfrom the glass composition comprising: SiO₂ from about 60 to about 63weight percent; Al₂O₃ from about 14 to about 16 weight percent; CaO fromabout 14 to about 16 weight percent; MgO from about 6 to about 8.5weight percent; Fe₂O₃ less than 1 weight percent; and TiO₂ less than 1weight percent. In some embodiments, the composition may besubstantially free of Li₂O. In some cases, the composition may furthercomprise Li₂O less than 0.5 weight percent. In some cases, Li₂O may bepresent in an amount greater than 0 weight percent and less than 0.5weight percent. In some embodiments, the (Li₂O+MgO+Al₂O₃) content of thecomposition may range from about 22 up to 24 weight percent. In someembodiments, the a ratio of CaO to MgO (CaO/MgO) of the composition mayrange from about 1.7 to about 2.0. In some cases, the composition may besubstantially free of F₂. In some cases, the composition may furthercomprise up to 0.2 weight percent Na₂O. In some cases, the compositionmay further comprise up to 0.2 weight percent K₂O. In some cases, RE₂O₃may be present in the composition in an amount greater than 0 weightpercent and less than 1 weight percent.

Some embodiments of the present invention relate to fabrics comprisingat least one fiber glass strand as disclosed herein. In someembodiments, the fabric may be woven. In other embodiments, the fabricmay be non-woven. In some embodiments, a fabric may comprise theplurality of glass fibers of any one of the glass compositions describedherein. For example, in some embodiments, a fabric may comprise aplurality of glass fibers formed from the glass composition comprising:SiO₂ from about 60 to about 63 weight percent; Al₂O₃ from about 14 toabout 16 weight percent; CaO from about 14 to about 16 weight percent;MgO from about 6 to about 8.5 weight percent; Fe₂O₃ less than 1 weightpercent; and TiO₂ less than 1 weight percent. In some embodiments, thecomposition may be substantially free of Li₂O. In some cases, thecomposition may further comprise Li₂O less than 0.5 weight percent. Insome cases, Li₂O may be present in an amount greater than 0 weightpercent and less than 0.5 weight percent. In some embodiments, the(Li₂O+MgO+Al₂O₃) content of the composition may range from about 22 upto 24 weight percent. In some embodiments, the a ratio of CaO to MgO(CaO/MgO) of the composition may range from about 1.7 to about 2.0. Insome cases, the composition may be substantially free of F₂. In somecases, the composition may further comprise up to 0.2 weight percentNa₂O. In some cases, the composition may further comprise up to 0.2weight percent K₂O. In some cases, RE₂O₃ may be present in thecomposition in an amount greater than 0 weight percent and less than 1weight percent.

In some embodiments of the present invention comprising a fabric, theglass fiber fabric may be a fabric woven in accordance with industrialfabric style no. 7781. In other embodiments, the fabric comprises aplain weave fabric, a twill fabric, a crowfoot fabric, a satin weavefabric, a stitch bonded fabric (also known as a non-crimp fabric), or a“three-dimensional” woven fabric.

Some embodiments of the present invention relate to composites. In someembodiments, a polymeric composite may comprise a polymeric material anda plurality of glass fibers formed from a glass composition describedherein. For example, in some embodiments, a polymeric composite maycomprise a polymeric material and a plurality of glass fibers formedfrom the glass composition comprising: SiO₂ from about 59 to about 63weight percent; Al₂O₃ from about 13.7 to about 16 weight percent; CaOfrom about 14 to about 16.5 weight percent; MgO from about 6 to about8.5 weight percent; Fe₂O₃ less than 1 weight percent; and TiO₂ less than1 weight percent. In some embodiments, the composition may besubstantially free of Li₂O. In some cases, the composition may furthercomprise Li₂O less than 0.5 weight percent. In some cases, Li₂O may bepresent in an amount greater than 0 weight percent and less than 0.5weight percent. In some embodiments, the (Li₂O+MgO+Al₂O₃) content of thecomposition may range from about 22 up to 24 weight percent. In someembodiments, the a ratio of CaO to MgO (CaO/MgO) of the composition mayrange from about 1.7 to about 2.0. In some cases, the composition may besubstantially free of F₂. In some cases, the composition may furthercomprise up to 0.2 weight percent Na₂O. In some cases, the compositionmay further comprise up to 0.2 weight percent K₂O. In some cases, RE₂O₃may be present in the composition in an amount greater than 0 weightpercent and less than 1.5 weight percent. In some embodiments, theplurality of glass fibers may be in the form of a non-woven fabric. Insome embodiments, the plurality of glass fibers may be in the form of awoven fabric. In some embodiments, the polymeric material may comprise athermoplastic polymer. In some embodiments, the polymeric material maycomprise a thermosetting polymer.

In other embodiments, a composite of the present invention may comprisea polymeric resin and a plurality of glass fibers disposed in thepolymeric resin, wherein at least one of the plurality of glass fiberswas formed from one of the other glass compositions disclosed herein aspart of the present invention. In some embodiments, a composite maycomprise a polymeric resin and at least one fiber glass strand asdisclosed herein disposed in the polymeric resin. In some embodiments, acomposite may comprise a polymeric resin and at least a portion of aroving comprising at least one fiber glass strand as disclosed hereindisposed in the polymeric resin. In other embodiments, a composite maycomprise a polymeric resin and at least one yarn as disclosed hereindisposed in the polymeric resin. In still other embodiments, a compositemay comprise a polymeric resin and at least one fabric as disclosedherein disposed in the polymeric resin. In some embodiments, a compositemay comprise at least one fill yarn comprising at least one fiber glassstrand as disclosed herein and at least one warp yarn comprising atleast one fiber glass strand as disclosed herein.

Composites of the present invention can comprise various polymericresins, depending on the desired properties and applications. In someembodiments, the polymeric resin may comprise an epoxy resin. In otherembodiments, the polymeric resin may comprise polyethylene,polypropylene, polyamide, polyimide, polybutylene terephthalate,polycarbonate, thermoplastic polyurethane, phenolic, polyester, vinylester, polydicyclopentadiene, polyphenylene sulfide, polyether etherketone, cyanate esters, bis-maleimides, or thermoset polyurethaneresins.

In certain embodiments, an article of manufacture may comprise aplurality of glass fibers formed from the glass composition of any oneof the compositions described herein. For example, in some embodiments,an article of manufacture may comprise a plurality of glass fibersformed from the glass composition comprising: SiO₂ from about 60 toabout 63 weight percent; Al₂O₃ from about 14 to about 16 weight percent;CaO from about 14 to about 16 weight percent; MgO from about 6 to about8.5 weight percent; Fe₂O₃ less than 1 weight percent; and TiO₂ less than1 weight percent. In some embodiments, the composition may besubstantially free of Li₂O. In some cases, the composition may furthercomprise Li₂O less than 0.5 weight percent. In some cases, Li₂O may bepresent in an amount greater than 0 weight percent and less than 0.5weight percent. In some embodiments, the (Li₂O+MgO+Al₂O₃) content of thecomposition may range from about 22 up to 24 weight percent. In someembodiments, the a ratio of CaO to MgO (CaO/MgO) of the composition mayrange from about 1.7 to about 2.0. In some cases, the composition may besubstantially free of F₂. In some cases, the composition may furthercomprise up to 0.2 weight percent Na₂O. In some cases, the compositionmay further comprise up to 0.2 weight percent K₂O. In some cases, RE₂O₃may be present in the composition in an amount greater than 0 weightpercent and less than 1 weight percent. In some embodiments, theplurality of glass fibers may be in the form of a non-woven fabric. Insome embodiments, the plurality of glass fibers may be in the form of awoven fabric.

In other embodiments, an article of manufacture may comprise a polymericmaterial and a plurality of glass fibers formed from the glasscomposition comprising: SiO₂ from about 59 to about 63 weight percent;Al₂O₃ from about 13.7 to about 16.5 weight percent; CaO from about 14 toabout 16.5 weight percent; MgO from about 6 to about 8.5 weight percent;Fe₂O₃ less than 1 weight percent; and TiO₂ less than 1 weight percent.In some embodiments, the composition may be substantially free of Li₂O.In some cases, the composition may further comprise Li₂O less than 0.5weight percent. In some cases, Li₂O may be present in an amount greaterthan 0 weight percent and less than 0.5 weight percent. In someembodiments, the (Li₂O+MgO+Al₂O₃) content of the composition may rangefrom about 22 up to 24 weight percent. In some embodiments, the a ratioof CaO to MgO (CaO/MgO) of the composition may range from about 1.7 toabout 2.0. In some cases, the composition may be substantially free ofF₂. In some cases, the composition may further comprise up to 0.2 weightpercent Na₂O. In some cases, the composition may further comprise up to0.2 weight percent K₂O. In some cases, RE₂O₃ may be present in thecomposition in an amount greater than 0 weight percent and less than 1.5weight percent. In some embodiments, the plurality of glass fibers maybe in the form of a non-woven fabric. In some embodiments, the pluralityof glass fibers may be in the form of a woven fabric. In someembodiments, the polymeric material may comprise a thermoplasticpolymer. In some embodiments, the polymeric material may comprise athermosetting polymer.

Some embodiments of the present invention relate to aerospacecomposites. In some embodiments, an aerospace composite may exhibitproperties desirable for use in aerospace applications, such as highstrength, high elongation, high modulus, and/or low density. In someembodiments, an aerospace composite may comprise a plurality of glassfibers from a glass composition described herein. For example, in someembodiments, an aerospace composite may comprise a polymeric materialand a plurality of glass fibers formed from the glass compositioncomprising: SiO₂ from about 60 to about 63 weight percent; Al₂O₃ fromabout 14 to about 16 weight percent; CaO from about 14 to about 16.5weight percent; MgO from about 6 to about 8.5 weight percent; Fe₂O₃ lessthan 1 weight percent; and TiO₂ less than 1 weight percent. In someembodiments, the composition may be substantially free of Li₂O. In somecases, the composition may further comprise Li₂O less than 0.5 weightpercent. In some cases, Li₂O may be present in an amount greater than 0weight percent and less than 0.5 weight percent. In some embodiments,the (Li₂O+MgO+Al₂O₃) content of the composition may range from about 22up to 24 weight percent. In some embodiments, the a ratio of CaO to MgO(CaO/MgO) of the composition may range from about 1.7 to about 2.0. Insome cases, the composition may be substantially free of F₂. In somecases, the composition may further comprise up to 0.2 weight percentNa₂O. In some cases, the composition may further comprise up to 0.2weight percent K₂O. In some cases, RE₂O₃ may be present in thecomposition in an amount greater than 0 weight percent and less than 1weight percent. In some embodiments, the plurality of glass fibers maybe in the form of a non-woven fabric. In some embodiments, the pluralityof glass fibers may be in the form of a woven fabric. In someembodiments, the polymeric material may comprise a thermoplasticpolymer. In some embodiments, the polymeric material may comprise athermosetting polymer.

Examples of components in which composites of the present inventionmight be used may include, but are not limited to, aerospace parts suchas floor panels, overhead bins, galleys, seat backs, and other internalcompartments that are potentially prone to impact, as well as externalcomponents such as helicopter rotor blades; automotive parts such asstructural components, bodies, and bumpers; wind energy components suchas wind turbine blades; high pressure vessels and/or tanks; safetyand/or security applications; high mechanical stress applications; highenergy impact applications such as ballistic or blast resistanceapplications; armor applications production of armor panels; casings formissiles and other explosive delivery devices; applications in the oiland gas industry, other applications related to transportation andinfrastructure, applications in alternative energy, high temperaturethermal insulation (i.e., thermal shielding) applications (due to higherstrength, higher modulus, higher softening temperature and higher glasstransition temperature). In some embodiments, a composite may havesheet-like physical dimensions or shape, and may be a panel.

Some embodiments of the present invention relate to prepregs. In someembodiments, a prepreg may comprise a plurality of glass fibers from aglass composition described herein. For example, in some embodiments, aprepreg may comprise a polymeric material and a plurality of glassfibers formed from the glass composition comprising: SiO₂ from about 60to about 63 weight percent; Al₂O₃ from about 14 to about 16 weightpercent; CaO from about 14 to about 16 weight percent; MgO from about 6to about 8.5 weight percent; Fe₂O₃ less than 1 weight percent; and TiO₂less than 1 weight percent. In some embodiments, the composition may besubstantially free of Li₂O. In some cases, the composition may furthercomprise Li₂O less than 0.5 weight percent. In some cases, Li₂O may bepresent in an amount greater than 0 weight percent and less than 0.5weight percent. In some embodiments, the (Li₂O+MgO+Al₂O₃) content of thecomposition may range from about 22 up to 24 weight percent. In someembodiments, the a ratio of CaO to MgO (CaO/MgO) of the composition mayrange from about 1.7 to about 2.0. In some cases, the composition may besubstantially free of F₂. In some cases, the composition may furthercomprise up to 0.2 weight percent Na₂O. In some cases, the compositionmay further comprise up to 0.2 weight percent K₂O. In some cases, RE₂O₃may be present in the composition in an amount greater than 0 weightpercent and less than 1 weight percent. In some embodiments, theplurality of glass fibers may be in the form of a non-woven fabric. Insome embodiments, the plurality of glass fibers may be in the form of awoven fabric. In some embodiments, the polymeric material may comprise athermoplastic polymer. In some embodiments, the polymeric material maycomprise a thermosetting polymer.

While many of the applications for the glass fibers described herein arereinforcement applications, some embodiments of glass fibers may beutilized in electronics applications such as printed circuit boards(“PCB”).

More particularly, some embodiments relate to glass fiber reinforcementsthat have electrical properties that permit enhancing performance of aPCB. For example, some embodiments may have a dielectric constant (Dk)desirable for electronics applications. The dielectric constant of amaterial (Dk), also known as “permittivity,” is a measure of the abilityof a material to store electric energy. A material to be used as acapacitor desirably has a relatively high Dk, whereas a material to beused as part of a PCB substrate desirably has a low Dk, particularly forhigh speed circuits. Dk is the ratio of the charge that would be stored(i.e., the capacitance) of a given material between two metal plates tothe amount of charge that would be stored by a void (air or vacuum)between the same two metal plates. As another example, some embodimentsmay have a coefficient for thermal expansion desirable for electronicsapplications. Accordingly, some embodiments may be used in a variety ofelectrical applications including, without limitation, printed circuitboards, precursors to printed circuit boards (e.g., fabrics, laminates,prepregs, etc.). In such embodiments, the printed circuit board or othercomposite to be used in electrical applications can comprise a polymericresin and a plurality of glass fibers in contact with the polymericresin, wherein at least one of the plurality of glass fibers was formedfrom any of the glass compositions disclosed herein as part of thepresent invention. The polymeric resin can include any of those known tothose of skill in the art for use in printed circuit boards or otherelectrical applications.

Turning now to methods of manufacturing glass fibers of the presentinvention and related products, glass fibers of the present inventioncan be prepared in the conventional manner well known in the art, byblending the raw materials used to supply the specific oxides that formthe composition of the fibers. Glass fibers according to the variousembodiments of the present invention can be formed using any processknown in the art for forming glass fibers, and more desirably, anyprocess known in the art for forming essentially continuous glassfibers. For example, although not limiting herein, the glass fibersaccording to non-limiting embodiments of the present invention can beformed using direct-melt or indirect-melt fiber forming methods. Thesemethods are well known in the art and further discussion thereof is notbelieved to be necessary in view of the present disclosure. See, e.g.,K. L. Loewenstein, The Manufacturing Technology of Continuous GlassFibers, 3rd Ed., Elsevier, N.Y., 1993 at pages 47-48 and 117-234.

Following formation of the glass fibers, a primary sizing compositioncan be applied to the glass fibers using any suitable method known toone of ordinary skill in the art. One skilled in the art may choose oneof many commercially available sizing compositions for the glass fibersbased upon a number of factors including, for example, performanceproperties of the sizing compositions, desired flexibility of theresulting fabric, cost, and other factors.

Fiber glass strands of the present invention can be prepared by anysuitable method known to one of ordinary skill in the art. Glass fiberfabrics of the present invention can generally be made by any suitablemethod known to one of ordinary skill in the art, such as but notlimited to interweaving weft yarns (also referred to as “fill yarns”)into a plurality of warp yarns.

Composites of the present invention can be prepared by any suitablemethod known to one of ordinary skill in the art, such as, but notlimited to, vacuum assisted resin infusion molding, extrusioncompounding, compression molding, resin transfer molding, filamentwinding, prepreg/autoclave curing, and pultrusion. Composites of thepresent invention can be prepared using such molding techniques as knownto those of ordinary skill in the art. In particular, embodiments ofcomposites of the present invention that incorporate woven fiber glassfabrics can be prepared using techniques known to those of skill in theart for preparation of such composites.

Prepregs of the present invention can be prepared by any suitable meansknown to one of ordinary skill in the art, such as but not limited topassing fiber glass strands, rovings, or fabrics through a resin bath;using a solvent-based resin; or using a resin film.

As noted above, composites of the present invention can comprise apolymeric resin, in some embodiments. A variety of polymeric resins maybe used. Polymeric resins that are known to be useful in reinforcementapplications can be particularly useful in some embodiments. In someembodiments, the polymeric resin may comprise a thermoset resin.Thermoset resin systems useful in some embodiments of the presentinvention may include, but are not limited to, epoxy resin systems,phenolic based resins, polyesters, vinyl esters, thermosetpolyurethanes, polydicyclopentadiene (pDCPD) resins, cyanate esters, andbis-maleimides. In some embodiments, the polymeric resin can comprise anepoxy resin. In other embodiments, the polymeric resin can comprise athermoplastic resin. Thermoplastic polymers useful in some embodimentsof the present invention include, but are not limited to, polyethylene,polypropylene, polyamides (including Nylon), polybutylene terephthalate,polycarbonate, thermoplastic polyurethanes (TPU), polyphenylenesulfides, and polyether ether keteone (PEEK). Non-limiting examples ofcommercially available polymeric resins useful in some embodiments ofthe present invention include EPIKOTE Resin MGS® RIMR 135 epoxy withEpikure MGS RIMH 1366 curing agent (available from Momentive SpecialtyChemicals Inc. of Columbus, Ohio), Applied Poleramic MMFCS2 epoxy(available from Applied Poleramic, Inc., Benicia, Calif.), and EP255modified epoxy (available from Barrday Composite Solutions, Millbury,Mass.).

The invention will be illustrated through the following series ofspecific embodiments. However, it will be understood by one of skill inthe art that many other embodiments are contemplated by the principlesof the invention.

EXAMPLES

Table 1 provides a plurality of fiberizable glass compositions accordingto various embodiments of the present invention as well as data relatingto various properties of such compositions. The glasses in theseexamples were made by melting mixtures of commercial and reagent gradechemicals (reagent grade chemicals were used only for the rare earthoxides) in powder form in 10% Rh/Pt crucibles at the temperaturesbetween 1500° C. and 1550° C. (2732° F.-2822° F.) for four hours. Eachbatch was about 1000 grams. After the 4 hour melting period, the moltenglass was poured onto a steel plate for quenching. Volatile species,such as alkali oxides from impurities in ingredients used, were notadjusted in the batches for their emission loss because of their lowconcentrations in the glasses. The compositions in the Examplesrepresent as-batched compositions. Commercial ingredients were used inpreparing the glasses. In the batch calculation, special raw materialretention factors were considered to calculate the oxides in each glass.The retention factors are based on years of glass batch melting andoxides yield in the glass as measured. Hence, the as-batchedcompositions illustrated in the examples are considered to be close tothe measured compositions.

Melt Properties

Melt viscosity as a function of temperature and liquidus temperature wasdetermined by using ASTM Test Method C965 “Standard Practice forMeasuring Viscosity of Glass Above the Softening Point,” and C829“Standard Practices for Measurement of Liquidus Temperature of Glass bythe Gradient Furnace Method,” respectively.

Table 1 includes measured liquidus temperature (T_(L)), referencetemperature of forming (T_(F)) defined by melt viscosity of 1000 Poisefor the glass compositions. The difference between the formingtemperature and the liquidus temperature (Delta T) is also shown.

Mechanical Properties

Young's modulus was also measured for certain glass compositions inTable 1 using the following technique. Approximately 50 grams of glasscullet having a composition corresponding to the appropriate exampleTable 1 was re-melted in a 90 Pt/10 Rh crucible for two hours at amelting temperature defined by 100 Poise. The crucible was subsequentlytransferred into a vertical tube, electrically heated furnace. Thefurnace temperature was preset at a fiber pulling temperature close orequal to a 1000 Poise melt viscosity. The glass was equilibrated at thetemperature for one hour before fiber drawing. The top of the fiberdrawing furnace had a cover with a center hole, above which awater-cooled copper coil was mounted to regulate the fiber cooling. Asilica rod was then manually dipped into the melt through the coolingcoil, and a fiber about 1-1.5 m long was drawn out and collected. Thediameter of the fiber ranged from about 100 μm at one end to about 1000μm at the other end.

TABLE 1 Oxide (wt. %) Ex 1 Ex 2 Ex 3 Ex 4 Ex 5 Ex 6 SiO₂ 60.71 61.7262.11 60.91 60.70 61.87 Al₂O₃ 14.21 14.26 14.65 14.24 15.49 14.22 Fe₂O₃0.30 0.30 0.31 0.28 0.29 0.30 CaO 15.37 14.81 14.30 15.24 14.52 14.69MgO 8.19 8.18 7.90 8.15 8.20 8.20 Na₂O 0.05 0.05 0.05 0.00 0.07 0.05 K₂O0.08 0.08 0.08 0.06 0.09 0.08 Y₂O₃ 0.50 0.00 0.00 0.50 0.00 0.00 F₂ 0.010.01 0.01 0.01 0.01 0.01 TiO₂ 0.57 0.58 0.59 0.61 0.62 0.58 Li₂O 0.000.00 0.00 0.00 0.00 0.00 Li₂O + MgO + Al₂O₃ 22.4 22.4 22.55 22.4 23.722.4 CaO/MgO 1.88 1.81 1.81 1.87 1.88 1.79 Al₂O3/(Al₂O₃ + CaO + MgO)0.38 0.38 0.40 0.38 0.41 0.38 SiO₂/Al₂O₃ 4.27 4.33 4.24 4.28 3.92 4.35Young's modulus, E (GPa) 88.7 88.7 88.1 88.1 88.5 88.4 Fiber density, d(g/cm3) 2.64 2.62 2.61 2.61 2.59 2.62 Liquidus, T_(L) (° C.) 1214 12201219 1225 1219 1217 Forming, T_(F) (° C.) 1289 1302 1314 1296 1299 1301Delta T (° C.) 75 82 95 71 80 84 Melting, T_(M) (° C.) 1475 1493 15081481 1489 1492 Oxide (wt. %) Ex 7 Ex 8 Ex 9 Ex 10 Ex 11 Ex 12 SiO₂ 61.2061.52 61.55 60.47 60.78 60.84 Al₂O₃ 14.24 14.11 14.01 14.16 14.53 14.86Fe₂O₃ 0.30 0.30 0.30 0.32 0.31 0.32 CaO 15.45 15.03 15.08 15.48 15.0714.78 MgO 8.10 8.32 8.35 8.23 8.15 8.11 Na₂O 0.05 0.05 0.05 0.12 0.060.06 K₂O 0.08 0.08 0.08 0.10 0.08 0.08 Y₂O₃ 0.00 0.00 0.00 0.49 0.370.25 F₂ 0.01 0.01 0.01 0.01 0.01 0.01 TiO₂ 0.58 0.57 0.57 0.61 0.58 0.59Li₂O 0.00 0.00 0.00 0.00 0.05 0.10 Li₂O + MgO + Al₂O₃ 22.3 22.4 22.422.4 22.7 23.1 CaO/MgO 1.91 1.81 1.81 1.88 1.85 1.82 Al₂O3/(Al₂O₃ +CaO + MgO) 0.38 0.38 0.37 0.37 0.38 0.39 SiO₂/Al₂O₃ 4.30 4.36 4.39 4.274.18 4.09 Young's modulus, E (GPa) 88.4 88.4 88.7 88.4 88.4 88.7 Fiberdensity, d (g/cm3) 2.63 2.63 2.63 2.63 2.64 2.63 Liquidus, T_(L) (° C.)1226 1216 1220 1199 1211 1209 Forming, T_(F) (° C.) 1287 1295 1295 12851289 1289 Delta T (° C.) 61 79 75 86 78 80 Melting, T_(M) (° C.) 14751483 1484 1472 1475 1477 Oxide (wt. %) Ex 13 Ex 14 Ex 15 Ex 16 Ex 17SiO₂ 60.91 60.97 60.57 62.45 60.92 Al₂O₃ 15.18 15.51 15.45 14.64 15.54Fe₂O₃ 0.32 0.33 0.32 0.27 0.29 CaO 14.49 14.20 14.49 13.73 15.83 MgO8.06 8.02 8.17 7.74 6.17 Na₂O 0.07 0.07 0.07 0.07 0.07 K₂O 0.08 0.080.09 0.08 0.09 Y₂O₃ 0.12 0.00 0.00 0.00 0.00 F₂ 0.01 0.01 0.01 0.01 0.01TiO₂ 0.60 0.61 0.62 0.59 0.63 Li₂O 0.15 0.20 0.22 0.41 0.44 Li₂O + MgO +Al₂O₃ 23.4 23.7 23.8 22.8 22.2 CaO/MgO 1.80 1.77 1.88 1.88 1.88Al₂O3/(Al₂O₃ + CaO + MgO) 0.40 0.41 0.41 0.41 0.41 SiO₂/Al₂O₃ 4.01 3.933.92 4.27 3.92 Young's modulus, E (GPa) 88.2 88.7 88.8 88.2 88.0 Fiberdensity, d (g/cm3) 2.63 2.62 2.60 2.59 2.64 Liquidus, T_(L) (° C.) 12031207 1199 1209 1210 Forming, T_(F) (° C.) 1290 1290 1291 1308 1293 DeltaT (° C.) 87 83 92 99 83 Melting, T_(M) (° C.) 1480 1481 1482 1513 1492Oxide (wt. %) Ex 18 Ex 19 Ex 20 Ex 21 SiO₂ 60.32 60.17 59.99 60.16 Al₂O₃14.23 14.35 14.31 14.29 Fe₂O₃ 0.34 0.34 0.34 0.34 CaO 15.37 15.20 15.1515.20 MgO 8.17 8.20 8.18 8.17 Na₂O 0.07 0.07 0.07 0.07 K₂O 0.08 0.080.08 0.08 Y₂O₃ 0.83 0.99 1.28 1.10 F₂ 0.01 0.01 0.01 0.01 TiO₂ 0.58 0.580.58 0.58 Li₂O 0.00 0.00 0.00 0.00 Li₂O + MgO + Al₂O₃ 22.4 22.6 22.522.5 CaO/MgO 1.88 1.88 1.88 1.88 Al₂O₃/(Al₂O₃ + CaO + MgO) 0.38 0.380.38 0.38 SiO₂/Al₂O₃ 4.23 4.19 4.19 4.21 Young's modulus, E (GPa) 89.188.5 88.5 88.0 Fiber density, d (g/cm3) 2.63 2.65 2.64 2.64 Liquidus,T_(L) (° C.) 1210 1211 1207 1211 Forming, T_(F) (° C.) 1287 1277 12801278 Delta T (° C.) 77 66 73 67 Melting, T_(M) (° C.) 1472 1461 14631464 Oxide (wt. %) Ex 22 Ex 23 Ex 24 Ex 25 SiO₂ 59.94 60.01 60.24 60.32Al₂O₃ 14.23 14.47 13.94 14.01 Fe₂O₃ 0.34 0.34 0.33 0.34 CaO 16.17 16.2216.11 15.55 MgO 8.02 7.66 8.11 8.19 Na₂O 0.07 0.07 0.07 0.11 K₂O 0.080.08 0.08 0.08 Y₂O₃ 0.56 0.58 0.56 0.87 F₂ 0.01 0.01 0.01 0.01 TiO₂ 0.580.58 0.56 0.51 Li₂O 0.00 0.00 0.00 0.00 Li₂O + MgO + Al₂O₃ 22.26 22.1422.05 22.15 CaO/MgO 2.02 2.12 1.99 1.88 Al₂O₃/(Al₂O₃ + CaO + MgO) 0.370.38 0.37 0.41 SiO₂/Al₂O₃ 4.21 4.15 4.32 4.3 Young's modulus, E (GPa)88.4 88.1 88.5 88.7 Fiber density, d (g/cm3) 2.65 2.65 2.64 2.63Liquidus, T_(L) (° C.) 1218 1213 1224 1217 Forming, T_(F) (° C.) 12801283 1276 1280 Delta T (° C.) 62 70 52 63 Melting, T_(M) (° C.) 14641468 1460 1457

Desirable characteristics that can be exhibited by various but notnecessarily all embodiments of the present invention can include, butare not limited to, the following: the provision of glass fibers, fiberglass strands, glass fiber fabrics, prepregs, and other products usefulfor reinforcement applications; and others.

Illustrative Embodiments of Suitable Compositions, Fibers, Composites,Products.

As used below, any reference to compositions, composites, or products isto understood as a reference to each of the those compositions,composites, or products disjunctively (e.g., “Illustrative embodiments1-4 is to be understood as illustrative embodiment 1, 2, 3, or 4”).

Illustrative embodiment 1 is a glass composition suitable for fiberforming comprising: SiO₂ from about 60 to about 63 weight percent, Al₂O₃from about 14 to about 16 weight percent, CaO from about 14 to about16.5 weight percent, MgO from about 6 to about 8.5 weight percent, Fe₂O₃less than 1 weight percent, TiO₂ less than 1 weight percent, wherein thecomposition is substantially free of Li₂O and the (Li₂O+MgO+Al₂O₃)content ranges from about 22 up to 24 weight percent.

Illustrative embodiment 2 is the composition of any preceding orsubsequent illustrative embodiment, wherein a ratio of CaO to MgO,(CaO/MgO), ranges from about 1.7 to about 2.0.

Illustrative embodiment 3 is the composition of any preceding orsubsequent illustrative embodiment, wherein a ratio of SiO₂ to Al₂O₃,(SiO₂/Al₂O₃), ranges from about 3.5 to about 4.5.

Illustrative embodiment 4 is the composition of any preceding orsubsequent illustrative embodiment, wherein the (Li₂O+MgO+Al₂O₃) contentranges from about 22 up to 23 weight percent.

Illustrative embodiment 5 is the composition of any preceding orsubsequent illustrative embodiment, wherein a ratio of Al₂O₃ to(Al₂O₃+MgO+CaO), (Al₂O₃/(Al₂O₃+MgO+CaO)), ranges from about 0.35 toabout 0.45.

Illustrative embodiment 6 is the composition of any preceding orsubsequent illustrative embodiment, wherein the composition issubstantially free of F₂.

Illustrative embodiment 7 is the composition of any preceding orsubsequent illustrative embodiment, further comprising up to 0.2 weightpercent Na₂O.

Illustrative embodiment 8 is the composition of any preceding orsubsequent illustrative embodiment, further comprising up to 0.2 weightpercent K₂O.

Illustrative embodiment 9 is a plurality of glass fibers formed from theglass composition of any of preceding or subsequent illustrativeembodiments.

Illustrative embodiment 10 is the plurality of glass fibers of anypreceding or subsequent illustrative embodiment, wherein the glassfibers have a modulus greater than 85 GPa.

Illustrative embodiment 11 is the plurality of glass fibers of anypreceding or subsequent illustrative embodiment, wherein the glassfibers have a density less than 2.7 g/cm³.

Illustrative embodiment 12 is the plurality of glass fibers of anypreceding or subsequent illustrative embodiment, wherein the glassfibers have a forming temperature (T_(F)) of less than 1350° C.

Illustrative embodiment 13 is the plurality of glass fibers of anypreceding or subsequent illustrative embodiment, wherein the glassfibers have a liquidus temperature (T_(L)) of less than 1250° C.

Illustrative embodiment 14 is a fiber glass strand comprising theplurality of glass fibers of any preceding or subsequent illustrativeembodiment.

Illustrative embodiment 15 is a roving comprising the plurality of glassfibers of any preceding or subsequent illustrative embodiment.

Illustrative embodiment 16 is a yarn comprising the plurality of glassfibers of any preceding or subsequent illustrative embodiment.

Illustrative embodiment 17 is a woven fabric comprising the plurality ofglass fibers of any preceding or subsequent illustrative embodiment.

Illustrative embodiment 18 is a non-woven fabric comprising theplurality of glass fibers of any preceding or subsequent illustrativeembodiment.

Illustrative embodiment 19 is a chopped fiber glass strand comprisingthe plurality of glass fibers of any preceding or subsequentillustrative embodiment.

Illustrative embodiment 20 is a polymeric composite comprising: apolymeric material; and a plurality of glass fibers formed from theglass composition of any preceding or subsequent illustrativeembodiment.

Illustrative embodiment 21 is the polymeric composite of any precedingor subsequent illustrative embodiment, wherein the plurality of glassfibers are in the form of a non-woven fabric.

Illustrative embodiment 22 is the polymeric composite of any precedingor subsequent illustrative embodiment, wherein the plurality of glassfibers are in the form of a woven fabric.

Illustrative embodiment 23 is the polymeric composite of any precedingor subsequent illustrative embodiment, wherein the polymeric materialcomprises a thermoplastic polymer.

Illustrative embodiment 24 is the polymeric composite of any precedingor subsequent illustrative embodiment, wherein the polymeric materialcomprises a thermosetting polymer.

Illustrative embodiment 25 is an article of manufacture comprising aplurality of glass fibers formed from the glass composition of anypreceding or subsequent illustrative embodiment.

Illustrative embodiment 26 is a glass composition suitable for fiberforming comprising: SiO₂ from about 60 to about 63 weight percent, Al₂O₃from about 14 to about 16 weight percent, CaO from about 14 to about16.5 weight percent, MgO from about 6 to about 8.5 weight percent, Fe₂O₃less than 1 weight percent, TiO₂ less than 1 weight percent, and RE₂O₃is present in an amount greater than 0 weight percent and less than 1weight percent, wherein the composition is substantially free of Li₂O.

Illustrative embodiment 27 is a glass composition suitable for fiberforming comprising: SiO₂ from about 59 to about 63 weight percent, Al₂O₃from about 13.7 to about 16 weight percent, CaO from about 14 to about16.5 weight percent, MgO from about 6 to about 8.5 weight percent, Fe₂O₃less than 1 weight percent, TiO₂ less than 1 weight percent, and RE₂O₃is present in an amount greater than 0 weight percent and less than 1.5weight percent, wherein the composition is substantially free of Li₂O.

Illustrative embodiment 28 is the glass composition of any preceding orsubsequent illustrative embodiment, wherein a ratio of SiO₂ to Al₂O₃,(SiO₂/Al₂O₃), ranges from about 3.6 to about 4.6.

Illustrative embodiment 29 is the glass composition of any preceding orsubsequent illustrative embodiment, wherein a ratio of Al₂O₃ to(Al₂O₃+MgO+CaO), (Al₂O₃/(Al₂O₃+MgO+CaO)), ranges from about 0.33 toabout 0.47.

Illustrative embodiment 30 is the glass composition of any preceding orsubsequent illustrative embodiment, wherein a ratio of CaO to MgO,(CaO/MgO), ranges from about 1.6 to about 2.8.

Illustrative embodiment 31 is a glass composition suitable for fiberforming comprising: SiO₂ from about 60 to about 63 weight percent, Al₂O₃from about 14 to about 16 weight percent, CaO from about 14 to about16.5 weight percent, MgO from about 6 to about 8.5 weight percent, Fe₂O₃less than 1 weight percent, TiO₂ less than 1 weight percent, Li₂O lessthan 0.5 weight percent, and RE₂O₃ is present in an amount greater than0 weight percent and less than 1 weight percent, wherein the(Li₂O+MgO+Al₂O₃) content ranges from about 22 up to 24 weight percent.

Illustrative embodiment 32 is a glass composition suitable for fiberforming comprising: SiO₂ from about 60 to about 63 weight percent, Al₂O₃from about 14 to about 16 weight percent, CaO from about 14 to about16.5 weight percent, MgO from about 6 to about 8.5 weight percent, Fe₂O₃less than 1 weight percent, TiO₂ less than 1 weight percent, and Li₂O ispresent in an amount greater than 0 weight percent and less than 0.5weight percent, wherein the (Li₂O+MgO+Al₂O₃) content ranges from about22 up to 23 weight percent.

Illustrative embodiment 33 is a plurality of glass fibers formed from aglass composition comprising: SiO₂ from about 60 to about 63 weightpercent, Al₂O₃ from about 14 to about 16 weight percent, CaO from about14 to about 16.5 weight percent, MgO from about 6 to about 8.5 weightpercent, Fe₂O₃ less than 1 weight percent, TiO₂ less than 1 weightpercent, and Li₂O is present in an amount greater than 0 weight percentand less than 0.5 weight percent, wherein the (Li₂O+MgO+Al₂O₃) contentranges from about 22 up to 24 weight percent, and the Young's modulus isgreater than 85 GPa.

Illustrative embodiment 34 is the plurality of glass fibers anypreceding or subsequent illustrative embodiment, wherein the Young'smodulus is greater than 88 GPa.

Illustrative embodiment 35 is any of the foregoing illustrativeembodiments, wherein the Al₂O₃/(Al₂O₃+MgO+CaO) ratio ranges between 0.35to 0.45.

Illustrative embodiment 36 is any of the foregoing illustrativeembodiments, wherein the Al₂O₃/(Al₂O₃+MgO+CaO) ratio is less than 0.40.

Illustrative embodiment 37 is any of the foregoing illustrativeembodiments, wherein the Al₂O₃/(Al₂O₃+MgO+CaO) ratio ranges from 0.37 to0.42.

Various embodiments of the invention have been described herein. Itshould be recognized that these embodiments are merely illustrative ofthe present invention. Variations of those preferred embodiments maybecome apparent to those of ordinary skill in the art upon reading theforegoing description. The inventors expect skilled artisans to employsuch variations as appropriate, and the inventors intend for theinvention to be practiced otherwise than as specifically describedherein. Accordingly, this invention includes all modifications andequivalents of the subject matter recited in the claims appended heretoas permitted by applicable law. Moreover, any combination of theabove-described elements in all possible variations thereof isencompassed by the invention unless otherwise indicated or otherwiseclearly contradicted by context.

It is to be understood that the present description illustrates aspectsof the invention relevant to a clear understanding of the invention.Certain aspects of the invention that would be apparent to those ofordinary skill in the art and that, therefore, would not facilitate abetter understanding of the invention have not been presented in orderto simplify the present description. Although the present invention hasbeen described in connection with certain embodiments, the presentinvention is not limited to the particular embodiments disclosed, but isintended to cover modifications that are within the spirit and scope ofthe invention.

What is claimed is:
 1. A glass composition suitable for fiber formingcomprising: SiO₂ from 60 to 63 weight percent; Al₂O₃ from 14 to 16weight percent; CaO from 14 to 16.5 weight percent; MgO from 6 to 8.5weight percent; Fe₂O₃ less than 1 weight percent; and TiO₂ less than 1weight percent, wherein the composition is substantially free of Li₂O,the (Li₂O+MgO+Al₂O₃) content ranges from 22 up to 24 weight percent, anda ratio of CaO to MgO, (CaO/MgO), ranges from 1.7 to 2.0.
 2. The glasscomposition of claim 1, further comprising up to 0.2 weight percentNa₂O.
 3. The glass composition of claim 1, further comprising up to 0.2weight percent K₂O.
 4. The glass composition of claim 1, wherein thecomposition is substantially free of F₂.
 5. The glass composition ofclaim 1, wherein the (Li₂O+MgO+Al₂O₃) content ranges from 22 up to 23weight percent.
 6. The glass composition of claim 1, wherein a ratio ofSiO₂ to Al₂O₃, (SiO₂/Al₂O₃), ranges from 3.5 to 4.5.
 7. The glasscomposition of claim 1, wherein a ratio of Al₂O₃ to (Al₂O₃+MgO+CaO),(Al₂O₃/(Al₂O₃+MgO+CaO)), ranges from 0.35 to 0.45.
 8. An article ofmanufacture comprising a plurality of glass fibers formed from the glasscomposition of claim
 1. 9. A plurality of glass fibers formed from theglass composition of claim
 1. 10. The plurality of glass fibers of claim9, wherein the glass fibers have a Young's modulus greater than 85 GPa.11. The plurality of glass fibers of claim 9, wherein the glass fibershave a density less than 2.7 g/cm³.
 12. The plurality of glass fibers ofclaim 9, wherein the glass fibers have a forming temperature (T_(F)) ofless than 1350° C.
 13. The plurality of glass fibers of claim 9, whereinthe glass fibers have a liquidus temperature (T_(L)) of less than 1250°C.
 14. A fiber glass strand comprising the plurality of glass fibers ofclaim
 9. 15. A roving comprising the plurality of glass fibers of claim9.
 16. A yarn comprising the plurality of glass fibers of claim
 9. 17. Awoven fabric comprising the plurality of glass fibers of claim
 9. 18. Anon-woven fabric comprising the plurality of glass fibers of claim 9.19. A chopped fiber glass strand comprising the plurality of glassfibers of claim
 9. 20. A polymeric composite comprising: a polymericmaterial; and a plurality of glass fibers formed from the glasscomposition of claim
 1. 21. The polymeric composite of claim 20, whereinthe plurality of glass fibers are in the form of a non-woven fabric. 22.The polymeric composite of claim 20, wherein the plurality of glassfibers are in the form of a woven fabric.
 23. The polymeric composite ofclaim 20, wherein the polymeric material comprises a thermoplasticpolymer.
 24. The polymeric composite of claim 20, wherein the polymericmaterial comprises a thermosetting polymer.
 25. A glass compositionsuitable for fiber forming comprising: SiO₂ from 59 to 63 weightpercent; Al₂O₃ from 13.7 to 16 weight percent; CaO from 14 to 16.5weight percent; MgO from 6 to 8.5 weight percent; Fe₂O₃ less than 1weight percent; TiO₂ less than 1 weight percent; and RE₂O₃ is present inan amount greater than 0 weight percent and less than 1.5 weightpercent, wherein the composition is substantially free of Li₂O.
 26. Theglass composition of claim 25, wherein a ratio of SiO₂ to Al₂O₃,(SiO₂/Al₂O₃), ranges from 3.6 to 4.6.
 27. The glass composition of claim25, wherein a ratio of CaO to MgO, (CaO/MgO), ranges from 1.6 to 2.8.28. The glass composition of claim 25, wherein a ratio of Al₂O₃ to(Al₂O₃+MgO+CaO), (Al₂O₃/(Al₂O₃+MgO+CaO)), ranges from 0.33 to 0.47. 29.A glass composition suitable for fiber forming comprising: SiO₂ from 60to 63 weight percent; Al₂O₃ from 14 to 16 weight percent; CaO from 14 to16.5 weight percent; MgO from 6 to 8.5 weight percent; Fe₂O₃ less than 1weight percent; TiO₂ less than 1 weight percent; Li₂O less than 0.5weight percent; and RE₂O₃ is present in an amount greater than 0 weightpercent and less than 1 weight percent, wherein the (Li₂O+MgO+Al₂O₃)content ranges from 22 up to 23.8 weight percent.